The present invention relates to a pencil having an axially-movable core, particularly a soft-core pencil, for example a cosmetic pencil. Pencils of this type have a sleeve-shaped pencil body with a front core opening, in which a core-driving part that holds the core is seated to move axially. In the known pencils, the pencil body comprises a shaft and a rotating sleeve that is rotatably connected to the shaft and forms the front part of the pencil body. The rotating sleeve is connected directly or indirectly to the core-driving part in the manner of a spindle drive. The core can be moved out of the core opening and back into it due to a relative rotation between the rotating sleeve and the shaft.
Typically, a protective cap that completely receives the rotating sleeve can be placed onto the shaft of such pencils. A pencil of this type, described in, for example, WO 96/18323, is disadvantageous in terms of handling. First, when the protective cap is removed, the core can easily be moved out of the core opening and may be broken off or deformed due to an accidental relative rotation between the shaft and the rotating sleeve. Likewise, in the application of an eyeliner pencil, an undesired relative rotation between the shaft and the front part is entirely possible, at least if the pencil is carelessly handled. Furthermore, relative rotation can occur between the shaft and the rotating sleeve even if the protective cap is in place. If, during a rotation of the protective cap, the cap is additionally bent transversely to the longitudinal axis of the pencil, the front part can be carried along by the rotating protective cap due to a frictional lockup, and the core can be pressed against the bottom of the cap and thus deformed. Moreover, in the conventional pencils, the rotatable connection between the front part and the shaft must be relatively stable, and therefore structurally complex, to assure the overall rigidity of the pencil. This connection often loosens over the service life of the pencil.
U.S. Pat. Nos. 1,489,765 and 2,336,328 disclose pencils in which the core can be moved out of an opening of the pencil body by a rod-shaped driving part that is axially seated in the pencil body and has an outside thread. The outside thread engages the inside thread of a drive nut that is axially fixedly seated in the pencil body and is accessible by way of an actuation window in the pencil body. In a pencil such as is shown in U.S. Pat. No. 2,720,863, the rear end of the core is seated in a core-retaining part, which has the shape of a tube section and is in turn inserted to be axially movable into a guide sleeve. The guide sleeve has a longitudinal slot through which radial protrusions of the core-retaining part project. The radial protrusions engage the inside thread of a drive nut that radially surrounds the guide sleeve. An actuating section of the drive nut projects beyond the circumference of the pencil body, and divides it into two sections, namely a shaft section and a tip section.
It is therefore the object of the present invention to provide a pencil of the type mentioned above, having an alternative construction and a particularly simple design, and small radial dimensions.